Sewing machine pneumatic needle threaders



Dec; 30, 1969 h. M. KAPLAN n I SEWING MACHINE PNEUMATIC NEEDLE THREADERSFiled July 10, 1967' 3 Sheets-Sheet 1 INVENTOR. Ronald M. Koplcm WITNESSAT ORNEY 3 Sheets-Sheet 2 INVENTOR. Ronald M. Kaplcm Dec. 30, 1969 R. M.KA'PLAN v SEWING MACHINE PNEUMATIC NEEDLE THREADERS Filed July 10, 1967WITNESS Dec. 30, 1969 R. M. KAPLAN SEWING MACHINE PNEUMATIC NEEDLETHREADERS Filed July 10. 1967 3 Sheets-Sheet 5 Fig.7.

Illa/l 1 INVENTOR. Ronald M. Kaplan Wifness v X TTQRNEY a J .m m 4United States Patent 3,486,472 SEWING MACHINE PNEUMATIC NEEDLE THREADERSRonald M. Kaplan, Cedar Grove, N.J., assignor to The Singer Company, NewYork, N.Y., a corporation of New Jersey Continuation-impart ofapplication Ser. No. 584,148,

Oct. 4, 1966. This application July 10, 1967, Ser.

Int. Cl. Db 87/00 US. Cl. 112-225 Claims ABSTRACT OF THE DISCLOSURE Thisdisclosure relates to a pneumatic needle threader adapted for use in asewing machine.

CROSS-REFERENCE TO RELATED APPLICATIONS This application is acontinuation-in-part of my copending application, Ser. No. 584,148,filed Oct. 4, 1966 and now abandoned for Vacuum Needle Threader forSewing Machines.

BACKGROUND OF THE INVENTION Heretofore, threading of the needle was doneby hand or with the aid of a guide or hook device. Either method hadobvious deficiencies ranging from the poor eyesight of the operator todoubling the thickness of the thread required to be drawn through theneedle. A primitive pneumatic device of the vacuum type was used whichhad some of the above disadvantages in that its positioning was left tothe operator, but further it required establishing an air seal at thepoint of contact. The pressure exerted in maintaining the sealundoubtedly caused the breaking of many needles and the resultant lossof the time sought to be saved.

SUMMARY OF THE INVENTION In accordance with the present invention, apneumatic needle threader adapted for use in a sewing machine having aframe provided with a head in which is journaled a needle bar withneedle eye reference means and carrying an eye pointed needle. Thepneumatic needle threader includes a pneumatic pump means and a leverhaving an orifice extending through one end. The lever is swung from apivot connection in the head to an operative position with its free endadjacent to the needle. In the operative position, orifice positioningmeans provided on the lever co-act with the needle eye reference meanson the needle bar to align the needle eye in proximity to the open endof the orifice. A conduit means connects the pneumatic pump and theorifice so that with the lever in the operative position, thread placedadjacent to said eye will be threaded through said eye on the operationof said pump means.

An object of the present invention is to provide an improved pneumaticneedle threader mechanism which overcomes the prior art disadvantages;which serves to thread the needle; which may be connected to the sewingmachine and stored out of sight ready for use; which may be accessiblefor use by opening the normally closed face plate of the head; whichuses a pivotally connected lever that is swung as much as 180 intooperative position; which positions needle eye reference means of .theneedle bar to align the needle eye into threading position Whileprotecting against needle breakage; and which insures placing the needleeye in proximity to an orifice in the free end of the lever.

Another object of this invention is to provide an improved pneumaticneedle threader mechanism which sub- 3,486,472 Patented Dec. 30, 1969stantially eliminates failure of the mechanism due to conduit breakageby minimizing the movement of the flexible conduit; which may use avacuum pump that is manually operated and spring loaded and adapted tobe mounted in the face plate; which may have a manual vacuum pumpcapable of being locked in the loaded position; which may have a switchoperated vacuum pump; which is simple, economical and reliable.

Other objects and advantages will be apparent from the followingdescription of several embodiments of the invention and the novelfeatures will be particularly pointed out hereinafter in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS This invention is illustrated in theaccompanying drawings in which:

FIGURE 1 is a vertical sectional view in part of the sewing machineshead embodying the invention with the lever in a stored inoperativeposition.

FIGURE 2 is a vertical sectional view in part of the sewing machineshead embodying the invention with the front plate open and the novelpneumatic needle threading mechanism in operative position.

FIGURE 3 is an exploded detailed view of the improved lever in operativeposition.

FIGURE 4 is an enlarged sectional view of the free end of the improvedlever taken along line 44 of FIG- URE 3.

FIGURE 5 is a front elevation in part of the free end of the improvedlever.

FIGURE 6 is a vertical section in part of the improved pneumatic pumptaken along line 66 of FIGURE 1.

I FIGURE 7 is a rear view, partly in section, of a sewing machine withthe face plate removed in which another embodiment of the presentinvention is illustrated.

FIGURE 8 is a sectional view taken along line 88 of FIGURE 7.

FIGURE 9 is a front vertical sectional view of the head of the sewingmachine illustrated in FIGURE 7.

DESCRIPTION OF THE INVENTION In the illustrated embodiments of theinvention the sewing machine may be of any conventional type, such as isshown in the drawings, particularly FIGURES 1, 2 and 7, having a bed 10,a standard 11 (see FIGURE 7) extending vertically from one end of bed 10and from which is cantilevered a bracket arm 12 that terminates in ahead 14 overhanging the bed.

The embodiment of the invention illustrated in FIG- URES l-6 and 7-9will be depicted in the same type of sewing machine in which the bracketarm 12 has a rib 16 into which bearing 18 is mounted. The actuatingshaft 20 is journaled in bearing 18 and has one of its ends connected toa source of rotatable power (not shown) and the other end has mountedthereon a counterbalanced crank 22. Crank pin 24 connects a needle barreciprocating link 26 and a needle thread take-up link 28 to thecounterbalanced crank 22. Crank pin 24 connects a needle barreciprocating link 26 and a needle thread take-up link 28 to thecounterbalanced crank 22. A take-up lever 30 is suitably connected tothe needle thread take-up link i 28 as by pin 32. Link pin 34 extendsfrom engagement On rotation of shaft 20 the connecting components 22 and26 will cause the vertical reciprocation of needle bar 36 and itsconnected needle 44.

Both bracket arm 12 and head 14 have an open top which is closed by acover 50 removably connected and fixedly held in place by screws 52,only one of which is shown, threaded into threaded hole 54 in rib 16.Cover 50 extends over the end of head 14 and this additional open areais closed by a substantially U shaped face plate 56 pivotally mounted asat 58. The normally closed position of face plate 56 is maintained by aspring catch 60 being yieldably engaged by a retaining spring 62connected to cover 50 by screw 64. Slight pressure will open face plate56 so as to provide ready access to the interior of head 14.

This invention is applicable to pneumatic forms of needle threading. Theembodiments of FIGURES l-6 and 7-9 depict vacuum type needle threaderswhich serve to draw the thread through the eye of the needle. However itwill be understood by those skilled in the art that the scope of thepresent invention extends to pneumatic needle threading by means ofblowing the thread into said eye so as to accomplish the pneumaticthreading of said eye. In other words though a vacuum pump has beenshown and described, it could readily be replaced by a blower typepneumatic pump with little or no modification of the other componentsand provide the pneumatic needle threading.

The embodiment of the novel pneumatic needle threader mechanism,generally designated as 66, is illustrated in FIGURES l-6 and has alever 68, a pneumatic pump means in the form of a vacuum pump 70 and aconduit means 72 connected therebetween.

A mounting plate 72 shown in FIGURE 3 is fixedly connected by two screws76 threaded into threaded holes 78 to the front vertical wall 80 of head14. Mounting plate 74 extends outwardly from its fixed connection over alow vertical side wall 82 formed integrally with bottom wall 42. Also, athird threaded hole 86 is partially overhung and somewhat larger thanholes 78, has its center serve as an axis of oscillation, designatedgenerally as 88, for lever 68. Lever 68 is pivotally connected to plate74 by a screw 90 passing through washer 92 and pivot hole 94 tothreadingly engage hole 86. This overhung pivot connection permits lever68 to describe an arc of approximately 180 about the axis of oscillation88 from its vertical upwardly extended stored inoperative position shownin FIGURE 1 from which after Opening of face plate 56, lever 68 is swungto the vertical downwardly extended operative position shown in FIGURE2.

The free end 96 of lever 68 has a web 98 that terminates in a rearwardlyextending flange 100, perpendicular to the stem 102 of lever 68. A foot104 is fixedly connected to flange 100' by screws 106 which pass throughholes 108 of flange 100 to thread into threaded hole 110 of foot 104.

Foot 104 as shown in FIGURES 3, 4 and has a frOnt section 112 thatextends from a shoulder 114. A conical entrance 116 is formed on frontsection 112 with the taper in the direction of the shoulder. The conicalentrance -116 leads to an orifice 118 that extends through foot 104 in aplane substantially perpendicular to stem 102.

A needle slot 120 having a tapered entrance 122 extends inwardly fromedge 124 of foot 104 in a plane normal to stem 102 and intersectsorifice 118. Needle slot 120 is so disposed that on placing lever 68 inthe operative position slot 120 will lie in the same vertical plane asdoes needle 44. This permits needle 44 to enter slot 120 on lever 68'being swung vertically downwardly to the operative position asdescribed more fully hereinafter.

A thread removal slot 126 lies in a plane substantially perpendicular tostem 102 and creates an opening from orifice 118 to edge 124 and fromslot 120 to shoulder 114.

The end of orifice 118 remote from shoulder 114 has a rigid conduit 128connected into counter-bore 130. Conduit 128 will extend from orifice118 along stem 102 in the direction of axis of rotation 88 adjacentwhich it will have its other end disposed. A flexible conduit 132 asshown in FIGURES 2 and 6 has one end fixedly disposed in a coupler 134connected into vacuum pump 70 and extends upwardly therefrom to ajunction (not shown) with rigid conduit 128 adjacent to the axis ofrotation 88.

.The rigid conduit 128 and flexible conduit 132 combine to make upconduit means 72. The possibilit of conduit wear or failure is reducedby having rigid conduit 128 travel with lever 68 and connect to flexibleconduit 132 immediately adjacent axis of rotation 88 so that theinterconnection remains in head 14. Also, the movement of the flexibleconduit 132 is limited to that corresponding to the small radiusmeasured from the junction to the axis, of rotation 88.

Intermediate the pivotal connection of lever 68 and foot 104 an orificepositioning means, generally designated 136, is disposed on lever 68 andincludes a seat lug 138 and a stop lug 140, each extending outwardlyfrom stem 102. The vertical distance between the bottom of the needleclamp 46 and the needle eye 48 is a fixed distance. The verticaldistance between the seating edge of seat lug 138 and orifice 118 ispredetermined to coincide with said fixed vertical distance. Thehorizontal distance between the edge of the needle clamp 46 to beabutted by stop lug 140 and the vertical axis of needle 44 is also afixed distance. The horizontal distance between the abutting edge ofstop lug 140 and orifice 118 is predetermined to coincide with saidfixed horizontal distance. Placing lever 68 in the operative positionwith needle clamp 46 seated on seat lug 138 and abutted by stop lug 140will cause needle 44 to be disposed in needle slot with needle eye 48 inalignment with and in proximity to orifice 118. Stop lug serves tonegate needle 44 breakage caused by excessive or over swinging of lever68 by preventing needle 44 from contacting the walls of slot 120.

Vacuum pump 70 as shown in FIGURES 1, 2 and 6 is mounted in face plate56 by screws 142 passing through holes 144 in its housing 146 to threadinto threaded holes 148 in the face plate.

A cylinder 150 as shown in FIGURE 6 is formed in housing 146 into whichis disposed a piston 152 in seallngly engagement therewith. A shoulder154 is formed in the lower portion of cylinder 150 to act as a stopwhich prevents piston 152 from further descent. The section belowshoulder 154 is of smaller diameter and defines a cavity 156. Coupler134 has a passage 158 which communicates cavity 156 with flexibleconduit 132. A compression coil spring 160 is disposed in cavity 156 andextends upwardly into the cylinder to engage piston 152. Piston 152 hasa yieldable upwardly extending annular edge 162 that sealingly engagescylinder 150. Rod 164 is formed integrally with piston 152 and has avertical downwardly extending lower section 166 and a vertical upwardlyextending upper section 168. The lower section 166 is disposed withinspring 160 to act as a retainer. The upper section 168 of rod 164terminates in an outwardly turned handle 170 below which a recess 172 isformed. The distance from the underside of piston 152 to the undersideof handle 170 coincides with the distance from shoulder 154 to the topof cylinder 150. A cylinder cover 174 having a round hole 176 ofslightly larger diameter than that of rod 164 so as not to bind thevertical travel rod 164 is connected to housing 146 by screws 178threaded into holes 180. With piston 152 abutting shoulder 154 to latchor lock vacuum pump 70 in this loaded position, the handle 170 is tiltedto engage cover 174 in recess 172 of rod 164. The yieldable edge 162permits such tilting without adversely effecting the sealing engagementof piston 152 and cylinder 150, The upward urging of spring 160 will actto press the lower edge of the recess 172 against cover 174 and preventaccidental unloading of the vacuum pump 70. To operate vacuum pump 70,the handle is placed vertically so as to remove the cover 174 fromrecess 172 thus permitting the compressed spring 160 to force piston 152in the upwarddirection and evacuates the cavity 156 and cylinder 150below the rising piston 152 to produce a vacuum condition in pump 70,conduit means 72 and orifice 118. The vacuum pump 70 can be reloaded bydepressing and latching the handle 170 to cover 174. Thread isintroduced into the conical entrance 116 and on unlatching handle 170the vacuum pump 70 will operate to suck the thread through the needleeye 48 and into orifice 118.to vacuum thread the needle, similar to thatdepicted in FIGURE 3.

To facilitate removal of the now threaded needle 44, a thread removalslot 126 permits the thread to exit from foot 104 while remaining in eye48 so that lever 68 may be swung to a vertical upwardly extended storedinoperative position in head 14 as shown in FIGURE 1. The end of thethread in orifice 118 and rigidconduit 128 will be withdrawn therefromon the rising of lever After the vacuum needle threader mechanism 66 hasperformed the vacuum threading of needle 44 the vacuum pump 70 can bereloaded by depressing and relatching handle 170. The face plate 56 willbe closed with the vacuum needle threader mechanism 66 stored in head 14in a manner which does not interfere with the sewing operation of themachine and wherein it will remain out of sight ready for its next use.

The embodiment of the novel pneumatic needle threader mechanism,generally designated as 200, is il lustrated in FIGURES 7, 8 and 9 andmay be assumed to be associated with the same type of sewing machine aswas the pneumatic needle threader mechanism 66.

Like reference characters shall be used in the embodiment of theinvention shown in FIGURES 7, 8 and 9 for like components shown andreferred to previously for the embodiment of the invention depicted inFIGURES l6.

The pneumatic needle threader mechanism 200 has a lever 202, a pneumaticpump in the form of an electrically operated vacuum pump 204 and aconduit means 206 connected therebetween.

The lever 202 as shown in FIGURES 8 and 9 is pivotally connected to thehead 14 by a shoulder screw 208 that passes through a hole in the lever202 and stop plate 210 to be threadedly received in the front verticalwall 80 thereof. Thus, in the present embodiment the center of shoulderscrew 208 will serve as the axis of oscillation.

The lever 202 does not have an overhung mounting but may still describean arc of approximately 180 about theaxis of oscillation because it ispivotally connected at the end of a short offset leg 212 that is formedperpendicular to and integrally with the main stem 214 of lever 202. Theinoperative position of lever 202 is illustrated in FIGURE 9 by thedotted representation of the same. From its stored position the lever202'will be swung downwardly until a stop lug 216 extending outwardlyfrom offset leg 212 comes into contact with the upper edge of stop plate210, in which position main stem 214 will be substantially vertical.

A seat lug 218 extends outwardly from stem 202 in the same direction asand parallel to offset leg 212. The seat lug 218 is located at the pointon stem 202 which'will on seating of the needle clamp 46 thereon permitthe eye (not shown) of needle 44 to be aligned with the orifice,designated generally as 118 for the same purposes as was describedhereinbefore. The orifice positioning means are defined by stop lug 216and seat lug 218 which coact with needle eye reference means defined bystop plate 210 and needle clamp 46.

Once again foot 104 will be suitably connected to flange formed at thefree end of lever 202. Reference may be had to FIGURES 3, 4 and 5 forthe details of construction of foot 104, and therefore need not berepeated. Foot 104 lies in a plane parallel to seat lug 218 and offsetleg 212. Over-swinging of lever 202 is prevented by stop lug 216 whichinsures the placing of stem 214 in parallel relationship to needle 44wherein on seating the needle clamp 46 on the seat lug 218 alignment ofthe needle 44 with the orifice 118 is automatic.

The conduit means 206 is made up of a rigid conduit 220 and a flexibleconduit 222 that are suitably connected to each other as at 224. Thefree end of rigid conduit 220 is connected to foot 104 in communicationwith orifice 118. The free end of flexible conduit 222 is connected tovacuum pump 204 in communication with diaphragm chamber 226 as shown inFIGURE 7. The conduit means 20-6-will be suitably affixed to the lever202 so as to prevent the end of rigid conduit 220 from becomingdisconnected from orifice 118.

FIGURE 7 shows the vacuum pump mounted on the top of the bed 10 on therear side of standard 11 with the manual switch 228 positioned on theside of standard 11 remote from needle 44, but still within convenientreach of the operator. Flexible conduit 222 is shown extendingexternally of standard 11 and most of bracket arm 12 before passingthrough hole 230 formed in bracket arm 12 near head 14. The flexibleconduit 222 after entering hole 230 will pass along the inner side ofthe rear wall of head 14 so as not to interfere with the normal sewingoperation while having sufficient play to permit oscillation of lever202 from its stored position to its operative position.

The switch 228 electrically connects or disconnects the vacuum pump 204which is of a conventional design and readily purchasable in the market.The type shown has a solenoid 232 which will alternately operate to drawone leg of an L shaped plate 234, the other leg of which is connected tothe diaphragm shaft 236. The shaft 236 and consequently the L shapedplate 234 are spring returned to an inoperative position so as to effecta pulsing of the diaphragm (not shown) during alternate operation ofsolenoid 232.

The lever 202 is normally in the raised stored position. Accordingly,the needle 44 may be vacuum threaded by opening face plate (not shown)and swinging lever 202 downwardly into its operative position with stoplug 216 abutting stop plate 210 and needle clamp 46 seated on seat lug218 thus aligning the eye of needle 44 with the orifice 118. Theoperator will place the thread adjacent the eye of the needle andorifice 118 and loosely hold it in this general area. The switch 228 isoperated to the on position to actuate the vacuum pump 204 either beforeor after placing the thread adjacent the needle eye. With pump 204 inoperation a continuous vacuum will exist outside of orifice 118. Thevacuum will draw the thread through the needle eye and into orifice 118.Thereafter the operator will flip the switch 228 to the off position toelectrically disconnect the vacuum pump 204.

Once needle 44 has been threaded and the vacuum pump 204 shut off, thelever 202 may be swung to its stored position within head 14, so that onclosing of the face plate the machine is ready to sew.

It will be understood therefore that various changes in the details,materials, arrangements of parts and operating conditions which havebeen herein described and illustrated in order to explain the nature ofthe invention may be made by those skilled in the art within theprinciples and scope of the invention.

Having thus set forth the nature of the invention, what I claim hereinis:

1. In a sewing machine having a frame provided with a head, a needle barjournaled in said head and carrying at its lower end an eye pointedneedle, needle-eye reference means on said needle-bar, a pneumaticneedle threader comprising:

(a) a lever having an orifice formed at one end,

(b) means pivotally connecting said lever, at the end thereof remotefrom the orifice, to said head to permit said lever to be inoperativelypositioned remote from the needle-eye and operatively positioned withthe orifice aligned with the needle-eye,

(c) pneumatic pump means,

(d) conduit means connecting said pump means to said orifice, and

(e) orifice positioning means provided on said lever fixedly to engagethe needle eye reference means to place the lever in operative positionwhereby thread placed adjacent to the needle eye will be threadedthrough said eye on the operation of said pump means.

2. The combination claimed in claim 1 wherein:

(a) the orifice positioning means including a seat lug and a stop lug,

(b) the seat lug extending from the lever to seat the needle-eyereference means thereon on the lever being placed in the operativeposition, whereby the needle-eye reference means is prevented from beinglowered out of position, and

(c) the stop lug adapted to prevent the lever from being overswung intothe needle on the lever being swung into operative position.

3. The combination claimed in claim 1 wherein:

(a) the lever disposed inside the head and adapted to be swungdownwardly in the direction of the needle to place it in the operativeposition,

(b) a needle slot formed in the end of the lever remote from the pivotalconnection and adapted to receive the needle on the lever being placedin the operative position,

(c) the needle slot intersecting the orifice, and

(d) a thread removal slot formed in the end of the lever remote from thepivotal connection and intersecting the needle slot whereby the threadedneedle may be withdrawn from the needle slot and orifice without removalof the thread from the needle-eye.

4. The combination claimed in claim 3 wherein:

(a) a foot formed on the end of the lever remote from the pivotalconnection,

(b) the orifice extending through the foot,

(c) the needle slot formed in the foot on the same side as thepositioning means, and intersecting the orifice,

(d) the thread removal slot formed in the foot adjacent to and inintersection with the needle slot, (e) a front section formed on thefoot and extending in the direction away from the conduit means, and

(f) a conical entrance to the orifice formed in the front section andadapted to funnel the thread in the direction of the orifice.

5. The combination claimed in claim 1 wherein:

(a) the conduit means including a rigid conduit and a flexible conduit,

(b) the rigid conduit connected at one end to the orifice to extendalong and be movable with the lever and having the other end disposedadjacent the pivotal connection of the lever, and

(c) the flexible conduit connected at one end of the pneumatic pump anddisposed within the head, and having the other end connected to theother end of the rigid conduit so that the swinging movement of thelever between inoperative position and operative position will only movethe junction of the flexible and rigid conduit through an arc of smallradius substantially within the head.

6. The combination claimed in claim 1 wherein:

(a) a face plate pivotally mounted to the head to be rotated between anopen and a closed position,

(b) the pneumatic pump defines a vacuum pump fixedly 5 connected to theface plate and accessible on opening of the face plate, and

(c) the lever disposed in the head in spaced relation to the pivotalmounting of the face plate to permit the lever to swing between theoperative and inoperative position on opening of the face plate.

7. The combination claimed in claim 6 wherein:

(a) a vertical wall formed on the side of the head opposite the faceplate, and

(b) the lever having its pivotal connection above and extended outwardlyfrom the vertical wall to normally extend in a vertical upwardly storedposition with the face plate closed and on opening of the face plate thelever adapted to be swung about 180 to a vertical downwardly operativeposition.

8. The combination claimed in claim 1 wherein:

(a) the pneumatic pump is vacuum operated and includes a housing, apiston and a spring,

(b) the housing defining an internal cylinder,

(c) the piston disposed in sealing engagement in the cylinder,

(d) a cover connected to the housing to cover the cylinder,

(e) a hole in the cover,

(f) a rod integrally formed with the piston and ex tending out of thehole in the cover,

(g) a recess formed in the rod to be normally disposed out of thecylinder and on lowering of the piston in the cylinder the recess to beengaged by the cover to prevent movement of the rod and piston,

(h) passage means formed in the housing adjacent the end thereof remotefrom the cover to connect that side of the cylinder to the conduit meansand orifice,

(i) the spring disposed on the passage means side of the piston wherebyon disengagement of the cover from the recess the spring to force thepiston upwardly to create a vacuum which acts to suck the thread throughthe eye and into the orifice.

9. The combination claimed in claim 8 wherein:

(a) the piston having an upturned annular edge yieldably engaging thecylinder,

(b) a shoulder formed in the lower end of the cylinder to define acavity of smaller diameter than the cylinder,

(c) the piston to abut the shoulder at the point of its lowest descent,and

(d) the recess disposed on the rod a distance from the piston equal tothe distance between the shoulder and the cover whereby on the pistonabutting the shoulder a tilting of the rod will engage the cover in therecess.

10. The combination claimed in claim 1 wherein:

(a) the pneumatic pump is disposed remote from the head, and

(b) a switch in circuit with the pneumatic pump to selectively rendersaid pump operative and inoperative.

References Cited UNITED STATES PATENTS 70 RICHARD J SCANLAN, JR.,Primary Examiner

